Clean-Clear Water Initiatives and Innovations
Excessive growths of blue-green algae (cyanobacteria) are a common problem in eutrophic (fertile) lakes world-wide. Many blue-green algae species (including non-scum formers) can also produce hepato- or neuro-toxins of health concern to humans and other warm-blooded animals. Thus, beaches and swimming areas on certain shorelines can periodically experience large densities of blue-green algae that are not only unaesthetic, but potentially harmful to human health. In collaboration with City of Madison, Dane County, and Department of Natural Resources, we have tested a variety of devices, called algal scum interceptor, deflector, and exclosure (ASIDE) system, to reduce the presence of algal scums at several public beaches. One of the effective devices is an enclosure at Brittingham Beach and Bernie Beach, Monona Bay; Mendota County Beach on Lake Mendota, and Goodland County Park Beach on Lake Waubesa. The exclosure consists of a flotation collar and full water depth curtain. The full water depth curtain provides a mean to separate the lake water from the inside beach water as to exclude unsafe lake water from contaminating the swimming area. Furthermore, a treatment system is used to pump water inside the swimming area which filters and disinfects beach water using a series sand filter and UV system. The clean, treated water is then returned to the swimming area while algae and other unwanted materials are backwashed based on system pressures to the sanitary sewer. Results can be seen at report here. To provide real-time information and test its effectiveness, a Real Time Water Imaging System (RTWIS) has been developed. Success of the new treatment system can refer to local media or news.